1 /** @file
2   Provides copy memory, fill memory, zero memory, and GUID functions.
3 
4   The Base Memory Library provides optimized implementations for common memory-based operations.
5   These functions should be used in place of coding your own loops to do equivalent common functions.
6   This allows optimized library implementations to help increase performance.
7 
8 Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
9 This program and the accompanying materials are licensed and made available under
10 the terms and conditions of the BSD License that accompanies this distribution.
11 The full text of the license may be found at
12 http://opensource.org/licenses/bsd-license.php.
13 
14 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
15 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
16 
17 **/
18 
19 #ifndef __BASE_MEMORY_LIB__
20 #define __BASE_MEMORY_LIB__
21 
22 /**
23   Copies a source buffer to a destination buffer, and returns the destination buffer.
24 
25   This function copies Length bytes from SourceBuffer to DestinationBuffer, and returns
26   DestinationBuffer.  The implementation must be reentrant, and it must handle the case
27   where SourceBuffer overlaps DestinationBuffer.
28 
29   If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then ASSERT().
30   If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().
31 
32   @param  DestinationBuffer   The pointer to the destination buffer of the memory copy.
33   @param  SourceBuffer        The pointer to the source buffer of the memory copy.
34   @param  Length              The number of bytes to copy from SourceBuffer to DestinationBuffer.
35 
36   @return DestinationBuffer.
37 
38 **/
39 VOID *
40 EFIAPI
41 CopyMem (
42   OUT VOID       *DestinationBuffer,
43   IN CONST VOID  *SourceBuffer,
44   IN UINTN       Length
45   );
46 
47 /**
48   Fills a target buffer with a byte value, and returns the target buffer.
49 
50   This function fills Length bytes of Buffer with Value, and returns Buffer.
51 
52   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
53 
54   @param  Buffer    The memory to set.
55   @param  Length    The number of bytes to set.
56   @param  Value     The value with which to fill Length bytes of Buffer.
57 
58   @return Buffer.
59 
60 **/
61 VOID *
62 EFIAPI
63 SetMem (
64   OUT VOID  *Buffer,
65   IN UINTN  Length,
66   IN UINT8  Value
67   );
68 
69 /**
70   Fills a target buffer with a 16-bit value, and returns the target buffer.
71 
72   This function fills Length bytes of Buffer with the 16-bit value specified by
73   Value, and returns Buffer. Value is repeated every 16-bits in for Length
74   bytes of Buffer.
75 
76   If Length > 0 and Buffer is NULL, then ASSERT().
77   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
78   If Buffer is not aligned on a 16-bit boundary, then ASSERT().
79   If Length is not aligned on a 16-bit boundary, then ASSERT().
80 
81   @param  Buffer  The pointer to the target buffer to fill.
82   @param  Length  The number of bytes in Buffer to fill.
83   @param  Value   The value with which to fill Length bytes of Buffer.
84 
85   @return Buffer.
86 
87 **/
88 VOID *
89 EFIAPI
90 SetMem16 (
91   OUT VOID   *Buffer,
92   IN UINTN   Length,
93   IN UINT16  Value
94   );
95 
96 /**
97   Fills a target buffer with a 32-bit value, and returns the target buffer.
98 
99   This function fills Length bytes of Buffer with the 32-bit value specified by
100   Value, and returns Buffer. Value is repeated every 32-bits in for Length
101   bytes of Buffer.
102 
103   If Length > 0 and Buffer is NULL, then ASSERT().
104   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
105   If Buffer is not aligned on a 32-bit boundary, then ASSERT().
106   If Length is not aligned on a 32-bit boundary, then ASSERT().
107 
108   @param  Buffer  The pointer to the target buffer to fill.
109   @param  Length  The number of bytes in Buffer to fill.
110   @param  Value   The value with which to fill Length bytes of Buffer.
111 
112   @return Buffer.
113 
114 **/
115 VOID *
116 EFIAPI
117 SetMem32 (
118   OUT VOID   *Buffer,
119   IN UINTN   Length,
120   IN UINT32  Value
121   );
122 
123 /**
124   Fills a target buffer with a 64-bit value, and returns the target buffer.
125 
126   This function fills Length bytes of Buffer with the 64-bit value specified by
127   Value, and returns Buffer. Value is repeated every 64-bits in for Length
128   bytes of Buffer.
129 
130   If Length > 0 and Buffer is NULL, then ASSERT().
131   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
132   If Buffer is not aligned on a 64-bit boundary, then ASSERT().
133   If Length is not aligned on a 64-bit boundary, then ASSERT().
134 
135   @param  Buffer  The pointer to the target buffer to fill.
136   @param  Length  The number of bytes in Buffer to fill.
137   @param  Value   The value with which to fill Length bytes of Buffer.
138 
139   @return Buffer.
140 
141 **/
142 VOID *
143 EFIAPI
144 SetMem64 (
145   OUT VOID   *Buffer,
146   IN UINTN   Length,
147   IN UINT64  Value
148   );
149 
150 /**
151   Fills a target buffer with a value that is size UINTN, and returns the target buffer.
152 
153   This function fills Length bytes of Buffer with the UINTN sized value specified by
154   Value, and returns Buffer. Value is repeated every sizeof(UINTN) bytes for Length
155   bytes of Buffer.
156 
157   If Length > 0 and Buffer is NULL, then ASSERT().
158   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
159   If Buffer is not aligned on a UINTN boundary, then ASSERT().
160   If Length is not aligned on a UINTN boundary, then ASSERT().
161 
162   @param  Buffer  The pointer to the target buffer to fill.
163   @param  Length  The number of bytes in Buffer to fill.
164   @param  Value   The value with which to fill Length bytes of Buffer.
165 
166   @return Buffer.
167 
168 **/
169 VOID *
170 EFIAPI
171 SetMemN (
172   OUT VOID  *Buffer,
173   IN UINTN  Length,
174   IN UINTN  Value
175   );
176 
177 /**
178   Fills a target buffer with zeros, and returns the target buffer.
179 
180   This function fills Length bytes of Buffer with zeros, and returns Buffer.
181 
182   If Length > 0 and Buffer is NULL, then ASSERT().
183   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
184 
185   @param  Buffer      The pointer to the target buffer to fill with zeros.
186   @param  Length      The number of bytes in Buffer to fill with zeros.
187 
188   @return Buffer.
189 
190 **/
191 VOID *
192 EFIAPI
193 ZeroMem (
194   OUT VOID  *Buffer,
195   IN UINTN  Length
196   );
197 
198 /**
199   Compares the contents of two buffers.
200 
201   This function compares Length bytes of SourceBuffer to Length bytes of DestinationBuffer.
202   If all Length bytes of the two buffers are identical, then 0 is returned.  Otherwise, the
203   value returned is the first mismatched byte in SourceBuffer subtracted from the first
204   mismatched byte in DestinationBuffer.
205 
206   If Length > 0 and DestinationBuffer is NULL, then ASSERT().
207   If Length > 0 and SourceBuffer is NULL, then ASSERT().
208   If Length is greater than (MAX_ADDRESS - DestinationBuffer + 1), then ASSERT().
209   If Length is greater than (MAX_ADDRESS - SourceBuffer + 1), then ASSERT().
210 
211   @param  DestinationBuffer The pointer to the destination buffer to compare.
212   @param  SourceBuffer      The pointer to the source buffer to compare.
213   @param  Length            The number of bytes to compare.
214 
215   @return 0                 All Length bytes of the two buffers are identical.
216   @retval Non-zero          The first mismatched byte in SourceBuffer subtracted from the first
217                             mismatched byte in DestinationBuffer.
218 
219 **/
220 INTN
221 EFIAPI
222 CompareMem (
223   IN CONST VOID  *DestinationBuffer,
224   IN CONST VOID  *SourceBuffer,
225   IN UINTN       Length
226   );
227 
228 /**
229   Scans a target buffer for an 8-bit value, and returns a pointer to the matching 8-bit value
230   in the target buffer.
231 
232   This function searches target the buffer specified by Buffer and Length from the lowest
233   address to the highest address for an 8-bit value that matches Value.  If a match is found,
234   then a pointer to the matching byte in the target buffer is returned.  If no match is found,
235   then NULL is returned.  If Length is 0, then NULL is returned.
236 
237   If Length > 0 and Buffer is NULL, then ASSERT().
238   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
239 
240   @param  Buffer      The pointer to the target buffer to scan.
241   @param  Length      The number of bytes in Buffer to scan.
242   @param  Value       The value to search for in the target buffer.
243 
244   @return A pointer to the matching byte in the target buffer, otherwise NULL.
245 
246 **/
247 VOID *
248 EFIAPI
249 ScanMem8 (
250   IN CONST VOID  *Buffer,
251   IN UINTN       Length,
252   IN UINT8       Value
253   );
254 
255 /**
256   Scans a target buffer for a 16-bit value, and returns a pointer to the matching 16-bit value
257   in the target buffer.
258 
259   This function searches target the buffer specified by Buffer and Length from the lowest
260   address to the highest address for a 16-bit value that matches Value.  If a match is found,
261   then a pointer to the matching byte in the target buffer is returned.  If no match is found,
262   then NULL is returned.  If Length is 0, then NULL is returned.
263 
264   If Length > 0 and Buffer is NULL, then ASSERT().
265   If Buffer is not aligned on a 16-bit boundary, then ASSERT().
266   If Length is not aligned on a 16-bit boundary, then ASSERT().
267   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
268 
269   @param  Buffer      The pointer to the target buffer to scan.
270   @param  Length      The number of bytes in Buffer to scan.
271   @param  Value       The value to search for in the target buffer.
272 
273   @return A pointer to the matching byte in the target buffer, otherwise NULL.
274 
275 **/
276 VOID *
277 EFIAPI
278 ScanMem16 (
279   IN CONST VOID  *Buffer,
280   IN UINTN       Length,
281   IN UINT16      Value
282   );
283 
284 /**
285   Scans a target buffer for a 32-bit value, and returns a pointer to the matching 32-bit value
286   in the target buffer.
287 
288   This function searches target the buffer specified by Buffer and Length from the lowest
289   address to the highest address for a 32-bit value that matches Value.  If a match is found,
290   then a pointer to the matching byte in the target buffer is returned.  If no match is found,
291   then NULL is returned.  If Length is 0, then NULL is returned.
292 
293   If Length > 0 and Buffer is NULL, then ASSERT().
294   If Buffer is not aligned on a 32-bit boundary, then ASSERT().
295   If Length is not aligned on a 32-bit boundary, then ASSERT().
296   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
297 
298   @param  Buffer      The pointer to the target buffer to scan.
299   @param  Length      The number of bytes in Buffer to scan.
300   @param  Value       The value to search for in the target buffer.
301 
302   @return A pointer to the matching byte in the target buffer, otherwise NULL.
303 
304 **/
305 VOID *
306 EFIAPI
307 ScanMem32 (
308   IN CONST VOID  *Buffer,
309   IN UINTN       Length,
310   IN UINT32      Value
311   );
312 
313 /**
314   Scans a target buffer for a 64-bit value, and returns a pointer to the matching 64-bit value
315   in the target buffer.
316 
317   This function searches target the buffer specified by Buffer and Length from the lowest
318   address to the highest address for a 64-bit value that matches Value.  If a match is found,
319   then a pointer to the matching byte in the target buffer is returned.  If no match is found,
320   then NULL is returned.  If Length is 0, then NULL is returned.
321 
322   If Length > 0 and Buffer is NULL, then ASSERT().
323   If Buffer is not aligned on a 64-bit boundary, then ASSERT().
324   If Length is not aligned on a 64-bit boundary, then ASSERT().
325   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
326 
327   @param  Buffer      The pointer to the target buffer to scan.
328   @param  Length      The number of bytes in Buffer to scan.
329   @param  Value       The value to search for in the target buffer.
330 
331   @return A pointer to the matching byte in the target buffer, otherwise NULL.
332 
333 **/
334 VOID *
335 EFIAPI
336 ScanMem64 (
337   IN CONST VOID  *Buffer,
338   IN UINTN       Length,
339   IN UINT64      Value
340   );
341 
342 /**
343   Scans a target buffer for a UINTN sized value, and returns a pointer to the matching
344   UINTN sized value in the target buffer.
345 
346   This function searches target the buffer specified by Buffer and Length from the lowest
347   address to the highest address for a UINTN sized value that matches Value.  If a match is found,
348   then a pointer to the matching byte in the target buffer is returned.  If no match is found,
349   then NULL is returned.  If Length is 0, then NULL is returned.
350 
351   If Length > 0 and Buffer is NULL, then ASSERT().
352   If Buffer is not aligned on a UINTN boundary, then ASSERT().
353   If Length is not aligned on a UINTN boundary, then ASSERT().
354   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
355 
356   @param  Buffer      The pointer to the target buffer to scan.
357   @param  Length      The number of bytes in Buffer to scan.
358   @param  Value       The value to search for in the target buffer.
359 
360   @return A pointer to the matching byte in the target buffer, otherwise NULL.
361 
362 **/
363 VOID *
364 EFIAPI
365 ScanMemN (
366   IN CONST VOID  *Buffer,
367   IN UINTN       Length,
368   IN UINTN       Value
369   );
370 
371 /**
372   Copies a source GUID to a destination GUID.
373 
374   This function copies the contents of the 128-bit GUID specified by SourceGuid to
375   DestinationGuid, and returns DestinationGuid.
376 
377   If DestinationGuid is NULL, then ASSERT().
378   If SourceGuid is NULL, then ASSERT().
379 
380   @param  DestinationGuid   The pointer to the destination GUID.
381   @param  SourceGuid        The pointer to the source GUID.
382 
383   @return DestinationGuid.
384 
385 **/
386 GUID *
387 EFIAPI
388 CopyGuid (
389   OUT GUID       *DestinationGuid,
390   IN CONST GUID  *SourceGuid
391   );
392 
393 /**
394   Compares two GUIDs.
395 
396   This function compares Guid1 to Guid2.  If the GUIDs are identical then TRUE is returned.
397   If there are any bit differences in the two GUIDs, then FALSE is returned.
398 
399   If Guid1 is NULL, then ASSERT().
400   If Guid2 is NULL, then ASSERT().
401 
402   @param  Guid1       A pointer to a 128 bit GUID.
403   @param  Guid2       A pointer to a 128 bit GUID.
404 
405   @retval TRUE        Guid1 and Guid2 are identical.
406   @retval FALSE       Guid1 and Guid2 are not identical.
407 
408 **/
409 BOOLEAN
410 EFIAPI
411 CompareGuid (
412   IN CONST GUID  *Guid1,
413   IN CONST GUID  *Guid2
414   );
415 
416 /**
417   Scans a target buffer for a GUID, and returns a pointer to the matching GUID
418   in the target buffer.
419 
420   This function searches target the buffer specified by Buffer and Length from
421   the lowest address to the highest address at 128-bit increments for the 128-bit
422   GUID value that matches Guid.  If a match is found, then a pointer to the matching
423   GUID in the target buffer is returned.  If no match is found, then NULL is returned.
424   If Length is 0, then NULL is returned.
425 
426   If Length > 0 and Buffer is NULL, then ASSERT().
427   If Buffer is not aligned on a 32-bit boundary, then ASSERT().
428   If Length is not aligned on a 128-bit boundary, then ASSERT().
429   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
430 
431   @param  Buffer  The pointer to the target buffer to scan.
432   @param  Length  The number of bytes in Buffer to scan.
433   @param  Guid    The value to search for in the target buffer.
434 
435   @return A pointer to the matching Guid in the target buffer, otherwise NULL.
436 
437 **/
438 VOID *
439 EFIAPI
440 ScanGuid (
441   IN CONST VOID  *Buffer,
442   IN UINTN       Length,
443   IN CONST GUID  *Guid
444   );
445 
446 /**
447   Checks if the given GUID is a zero GUID.
448 
449   This function checks whether the given GUID is a zero GUID. If the GUID is
450   identical to a zero GUID then TRUE is returned. Otherwise, FALSE is returned.
451 
452   If Guid is NULL, then ASSERT().
453 
454   @param  Guid        The pointer to a 128 bit GUID.
455 
456   @retval TRUE        Guid is a zero GUID.
457   @retval FALSE       Guid is not a zero GUID.
458 
459 **/
460 BOOLEAN
461 EFIAPI
462 IsZeroGuid (
463   IN CONST GUID  *Guid
464   );
465 
466 /**
467   Checks if the contents of a buffer are all zeros.
468 
469   This function checks whether the contents of a buffer are all zeros. If the
470   contents are all zeros, return TRUE. Otherwise, return FALSE.
471 
472   If Length > 0 and Buffer is NULL, then ASSERT().
473   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
474 
475   @param  Buffer      The pointer to the buffer to be checked.
476   @param  Length      The size of the buffer (in bytes) to be checked.
477 
478   @retval TRUE        Contents of the buffer are all zeros.
479   @retval FALSE       Contents of the buffer are not all zeros.
480 
481 **/
482 BOOLEAN
483 EFIAPI
484 IsZeroBuffer (
485   IN CONST VOID  *Buffer,
486   IN UINTN       Length
487   );
488 
489 #endif
490